Method and anastomotic instrument for use when performing an end-to-side anastomosis

ABSTRACT

A method and apparatus for establishing an end-to-side anastomosis by using an instrument (501) is disclosed. The instrument has a passage (502D) for a bypass vessel, terminated by a circumferential anvil (502A, 503B), about which the end of the bypass vessel may be everted and then inserted through an anastomosis opening in a second vessel, such as a coronary artery. After insertion, the tissue edges to be joined are first clamped together by clamping slides (505) and then stapled together by stapling plungers (506) so as to interconnect the two vessels. The stapling plungers (506) are arranged to move at an angle to the passage (502D) instead of parallel to it. With this arrangement, it is possible to use a greater number of staples than has been possible in previous related methods. Preferably also, the instrument is adapted to be divided lengthwise of the passage (502D).

TECHNICAL FIELD

The present invention relates to a method of connecting an end region ofa first vessel to the side of a second vessel by carrying out anend-to-side anastomosis.

BACKGROUND ART

A method of this kind is described in the international applicationPCT/DK95/00430. In this previous method, the stapling plungers as wellas the associated clamping members were adapted to move in directionssubstantially parallel to the passage, in which the graft vessel wasplaced in readiness for establishing an end-to-side anastomosis withe.g. a coronary artery. With such an arrangement, the number of staplesas well as their mutual closeness were limited by the purely mechanicalneed for guiding the stapling plungers in their operative movement, withthe result that in the "seam" connecting the two vessels, there could besubstantial distances between adjacent staples.

DISCLOSURE OF THE INVENTION

It is the object of the present invention to provide a method of thekind referred to above, with which it is possible to use the instrumentfor establishing anastomoses with a greater number of staples and withsmaller distances between adjacent staples than has been possible withthe previously known method referred to above. This object is achievedby proceeding as set forth hereinbelow. In this manner, the guidewaysfor the stapling plungers will mostly be situated at a greater "radius"than the staple-bending recesses, so that there is ample space forforming these guideways in a greater number than previously, to convergeat very small mutual distances at the staple-bending recesses in theanvil.

The present invention also relates to an anastomotic instrument forcarrying out the method according to the invention, and this instrumentis characterized by the anastomotic instrument also describedhereinbelow.

Advantageous embodiments of the method and the anastomotic instrumentaccording to the invention, the effects of which--beyond what isself-evident--are explained in the following detailed part of thepresent description.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following detailed part of the present description, the inventionwill be explained in more detail with reference to the exemplaryembodiments of an anastomotic instrument according to the inventionshown in the drawings, in which

FIGS. 1-8 show the process of performing an end-to-side anastomosisusing an anastomotic instrument according to the invention subject ofthe application PCT/DK95/00430 referred to initially, FIGS. 1-7 beingdrawn in a highly simplified manner for ease of understanding,

FIGS. 9-11 in perspective and with certain parts cut away show apractical embodiment of an anastomotic instrument according to thepresent invention with the various possible relative positions of therelatively movable parts,

FIGS. 12-14 are side views of a staple-pusher set consisting of astapling plunger, a clamping slide and their common operating slide inpositions corresponding to those shown in FIG. 9-11, respectively.

FIG. 15 is a sectional side view of the complete instrument,

FIG. 16 is a sectional view taken along the line XVI--XVI in FIG. 15,

FIGS. 17-19 show a core member with associated anvil tube as viewed fromthe rear, side and front, respectively, and

FIGS. 20-22 show a housing likewise as viewed from the rear, side andfront, respectively.

Please note that the "front end" of the instrument is the end comprisingthe part in operation being in contact with the anastomosis beingestablished, in this case the anvil 503A, 503B.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As mentioned above, the embodiment shown in FIGS. 1-8 of the anastomosisinstrument according to the invention subject of the applicationPCT/DK95/00430 constitutes a simplified version with the primary purposeof explaining the invention; this does not, however, preclude thepossibility of using this embodiment in actual practice.

Thus, FIG. 1 shows an anastomosis instrument 1 consisting of three maincomponents that are movable relative to each other in the longitudinaldirection, i.e. in the direction shown as the vertical direction in FIG.1:

an anvil tube 2,

a clamping tube 5, and

a set of stapling plungers 6.

On its lower end, the anvil tube 2 carries an anvil 3, the upper side ofwhich is provided with a number of staple-bending recesses 4 adapted tocooperate with and bend an equal number of staples 7, in the situationshown in FIG. 1 being temporarily held lightly in an equal number ofstaple-holding recesses 8 formed in the lower ends of the staplingplungers 6.

FIG. 2 shows the situation, in which the instrument is made ready foruse by the operating surgeon. As mentioned initially, the anastomosisinstrument shown is primarily developed for use when performing coronarybypass operations, and to this end, a bypass vessel 9--that may be avein taken from some other part of the patient's body--has been insertedin the anvil tube with its lower end everted about the anvil 3 and withits end region 10 covering the staple-bending recesses 4 in the uppersurface of the anvil 3. At this point it should be noted that the bypassvessel 9 may have a considerably larger circumference than the inside ofthe anvil tube 2, consequently lying more or less folded in thelongitudinal direction in the latter, for which reason the action ofeverting its end region 10 about the anvil 3 does not necessarily entailundue stretching of the bypass vessel 9.

FIG. 3 shows the instrument having been made ready as shown in FIG. 2inserted in an opening in a coronary artery 11, said opening having anedge region 12 which, due to the elasticity of the tissue of thecoronary artery 11, will embrace the anvil tube 2 in a location close tothe anvil 3. The opening in the coronary artery 11 may e.g. have beenformed according to the method described in the internationalapplication with publication No. WO 95/17127 with the title "Method andinstrument for establishing the receiving side of a coronary arterybypass graft".

As soon as the operating surgeon in the situation shown in FIG. 3 hasascertained that the edge region 12 embraces the anvil tube 2 closely onall sides, he or she will proceed to the situation shown in FIG. 4, inwhich the clamping tube 5 has been moved towards the anvil 3 so as toclamp the edge region 12 on the coronary artery 11 and the end region 10on the bypass vessel 9 firmly together in readiness for the next stepshown in FIG. 5, in which the stapling plungers 6 have been moveddownwardly so as to cause the staples 7 to penetrate the edge region 12and the end region 10 and engage the staple-bending recesses 4, by whichthey will be bent inwards in a tangential direction in a similar mannerto what is known from both surgical staplers and ordinary officestaplers.

In the situation shown in FIG. 6, the clamping tube 5 together with thestapling plungers 6 have been moved outwardly and away from the staples7, the staple-holding recesses 8 due to their light holding actionhaving let go of the staples 7, the latter also having been anchored inthe end region 10 by their bent ends.

FIG. 7 shows the situation, in which the operation of removing theanastomosis instrument 1 from the coronary artery 11 and its anastomosiswith the bypass vessel 9 has begun. As will be seen from FIGS. 6 and 7,the circumferential pocket formed by the eversion of the lower end ofthe bypass vessel 9 will now open and allow the anvil 3 to be removed byluxation, FIG. 8 showing the situation after such removal, resulting ina finished anastomosis of the intima-to-intima type considered mostdesirable for this type of operation.

The three main components of the anastomosis instrument 1 referred toabove, i.e. the anvil tube 2, the clamping tube 5 and the set ofstapling plungers 6, will, of course, have to be connected to some kindof operating members to enable the operating surgeon and his or herassistants to carry out the steps shown in FIGS. 1-8. Theoretically,these operating members could consist of three tubes (not shown), viz.

a relatively long holding tube in continuation of the anvil tube 2,

a somewhat shorter clamping tube in continuation of the clamping tube 5,and

an even shorter stapling tube, to which the stapling plungers 6 areconnected.

As is well-known, however, coronary bypass operations, especiallyaccording to the method subject to the international application No. WO95/17127 entitled "Method and instrument for establishing the receivingsite of a coronary artery bypass graft", should be carried out asrapidly as possible, and for this reason, the "theoretical" embodimentshown in FIGS. 1-7 is too cumbersome to work with to ensure asufficiently rapid operating procedure. As mentioned above, FIGS. 9-22illustrate an embodiment of an anastomosis instrument according to thepresent invention, that is highly suitable for creating an end-to-sideanastomosis in a very short time.

In FIGS. 9-22, those of the components functionally corresponding tocomponents shown in FIGS. 1-7 have been given the same reference numberswith 500 added, whereas components not having "opposite numbers" inFIGS. 1-7 have been given the reference numbers of the components, withwhich they are most closely related, with the addition of a capitalletter.

As shown in FIG. 9, the anastomosis instrument 501 comprises a number ofparts functionally related to parts of the instrument shown in FIGS.1-7, viz.:

an anvil tube 502A, 502B,

an anvil 503A, 503B,

a set of clamping slides 505, slidable in

a clamping-slide housing 505A, 505B, and

a set of stapling plungers 506 slidable in said clamping slides 505.

Although the basic functions of these parts are the same as the basicfunctions of related parts in the embodiment of FIGS. 1-7, thearrangement differs somewhat from that of the latter, as will be evidentfrom the following.

Thus, the anvil tube 502A, 502B of FIG. 9 is an extension of a coremember 502CA, 502CB, cf. also FIG. 15, a central passage 502D extendingall the way through both the core member 502CA, 502CB and the anvil tube502A, 502B so as to make it possible to place a bypass vessel in thepassage in the same manner as shown in FIG. 2, showing a bypass vessel 9placed in the anvil tube 2.

The rear face of the anvil 503A, 503B, facing upwardly in FIG. 9, isprovided with a number of staple-bending recesses 504 substantiallyevenly distributed about the anvil and each adapted to co-operate with arespective one of the stapling plungers 506.

The clamping slides 505 are adapted to slide in a direction making anangle of substantially 30° with the longitudinal axis of the passage502D, being guided for such movement by guideways formed in the insideof the slide housing 505A, 505B and in the outside of the core member502CA, 502CB.

Similarly, each of the stapling plungers 506 is adapted to slide insubstantially the same direction in a guideway in a respective one ofthe clamping slides 505. Both the clamping slides 505 and the staplingplungers 506 are provided with short operating studs 505C and 506C,respectively, for co-operation with angular operating slots 505D formedin operating slides 505E adapted to slide in guideways formed in theinside of the slide housing 505A, 505B and in the outside of the coremember 502CA, 502CB in a direction substantially parallel to thelongitudinal axis of the passage 502D.

All the operating slides 505E are connected to a common operating head505F, the latter in turn being connected to one arm 505G of a pair oftongs 505G, 505H adapted to be operated manually by the surgeon, theother arm 505H being connected to the core member 502A, 502B and theclamping-slide housing 505A, 505B.

When an anastomosis is to be established according to the principlesexplained above with reference to FIGS. 1-8, the first step is, with themutually movable parts in the positions shown in FIGS. 9 and 12 and withthe stapling plungers 506 "loaded" with staples (not shown), to place abypass vessel in the passage 502D and evert its forward (lower) endabout the anvil 503A, 503B in the manner shown in FIG. 2. The next stepis to insert the anvil 503A, 503B with the everted end of the bypassvessel into an opening formed in the side of, say, a coronary artery inthe manner shown in FIG. 3. These two steps are suitably carried outusing the pair of tongs 505G, 505H as a "handle".

When the surgeon has ascertained that the bypass vessel is in thecorrect position relative to the artery, she or he will press the arm505G towards the arm 505H, thus causing the common operating head 505Fto move the operating slides 505E forward (downward), vide FIGS. 10 and13, so as to bring the clamping slides 505, moved by the co-operationbetween the oblique parts of the operating slots 505D and the operatingstuds 505C, close to the rear (upper) face of the anvil 503A, 503B, thuscreating a situation analogous to that shown in FIG. 4. At this point itshould, however, be noted that the oblique forward (downward) and inwardmovement of the clamping slides cause their forward end to exert acertain inwardly directed force on the tissues thus being clamped, thuscounteracting any tendency for these tissues to slip off from the anvil.

Continued movement of the arm 505G towards the "stationary" arm 505Hwill, of course, create further forward (downward) movement of theoperating slides 505E, vide FIGS. 11 and 14. The in-line parts of theoperating slots 505D will now hold the clamping slides 505 in a clampingposition, holding the tissues to be joined in the same manner as shownin FIG. 4, while the final part of the movement will cause the obliqueparts of the operating slots 505D to advance the stapling plungers 506and cause the latter to insert the staples (not shown) and bend them inco-operation (in contact) with the staple-bending recesses 504 in thesame manner as shown in FIG. 5. All of these recesses are (of course)placed at an outwardly directed angle of same substantially 30°.

At this point, the anastomosis has been established, after which theinstrument can be removed according to the principles illustrated byFIGS. 6-8, the surgeon previously having released the pressure on thearm 505G, allowing the spring 505I to act in the opposite direction,causing the parts 506, 505, 505E and 505F to return to the positionsshown in FIG. 9. If the core member 502CA, 502CB and the clamping slidehousing 505A, 505B were unitary components, i.e. each made in one piece,this removal would have to be effected by pulling the instrument awayfrom the anastomosis towards the free end of the bypass vessel (notshown). One prerequisite for so doing is, obviously, that such a freeend exists, i.e. that the bypass vessel is not part of an anastomosis atthe other end.

In order to make it possible to remove the instrument from a bypassvessel without a free end, the components surrounding it, i.e.surrounding the passage 502D, are constituted by downstream parts 502CA,505A and 503A and upstream parts 502CB, 505B and 503B, respectively ofthe core member, the clamping-slide housing and the anvil, respectively.(The expressions "upstream" and "downstream" refer to the direction offlow in the coronary artery being operated upon when the instrument isplaced in the preferred orientation relative to the artery, i.e. withthe blood flowing towards the left in FIG. 15).

The upstream part 505B of the housing 505A, 505B is releasably connectedto the downstream part 505A by means of hook-and-pin connections, cf.FIGS. 9, 16 and 21, constituted by recesses 505AB in the downstream part505A adapted to receive projections 505BB on the upstream part, holdingslots 505AC and 505BC being formed in alignment with the recesses 505ABand the projections 505BB, respectively, and adapted to receiveremovable holding pins 505K.

When the core member 502CA, 502CB and the clamping-slide housing 505A,505B are assembled with the holding pins 505K in place as shown in FIGS.9 and 16, the housing 505A, 505B will keep the core member 502CA, 502CBfrom coming apart. Conversely, when the holding pins 505K have beenpulled up, both the housing 505A, 505B and the core member 502CA, 502CBcan easily be divided by simply pulling them apart, thus making itpossible to remove the apparatus from the bypass vessel in a lateraldirection. During this operation of dividing the core member and thehousing, the various parts associated with them will, of course, have tobe divided or liberated. The means for achieving this are not shown indetail, as any normally skilled mechanical technician or toolmakershould be able to devise the requisite mechanism without furtherguidance from the present description.

What is claimed is:
 1. A method of connecting an end region of a firstvessel to a side of a second vessel by carrying out an end-to-sideanastomosis, said method comprising the steps a-d:a) forming an openingin the side of said second vessel, b) inserting in said opening ananastomosis instrument carrying said first vessel in a longitudinalcavity thereof and with said end region everted about a circumferentialanvil member constituting a forward portion of said instrument in such amanner that the intima side of said end region comes into contact withthe intima side of said second vessel at an edge region of said opening,c) joining said end region to said edge region by insertingpenetratingly therethrough and leaving therein a plurality of spikedmembers, and d) removing said instrument from the joint formed betweensaid first and second vessels,said steps a-d being carried out by e) theuse of said anastomosis instrument comprisinge1) an anvil assemblycomprising said circumferential anvil member and in which said firstvessel may be placed with its end region everted about said anvil memberwith the terminal part of said end region facing rearwardly, e2)rearwardly facing staple-bending recesses provided in said anvil member,e3) clamping members adapted to be moved towards said anvil member so asto make it possible to clamp together therebetween said end region onsaid first vessel and an edge region on said second vessel, and e4)stapling plungers movable relative to said anvil member and adapted toinsert staples penetratingly through said clamped end and edge regionsinto engagement with said stapling-bending recesses so as to bendpermanently said staples into a shape by which said staples hold saidend and edge regions together,characterized by f) said joining stepincluding the step of sliding said stapling plungers in directionsforming acute angles with the longitudinal axis of said longitudinalcavity so that said staples converge in a region forward of saidcircumferential anvil member.
 2. A method of connecting as claimed inclaim 1, wherein said joining step further includes the step of slidingsaid clamping members at acute angles parallel to those in whichadjacent ones of said stapling plungers are slidable.
 3. A method ofconnecting as claimed in claim 1, surrounding said passage arereleasably intereconnected so as to enable said passage to be splitlengthwise,wherein said anvil assembly and said clamping memberssurrounding said longitudinal cavity are respectively formed of tworeleasably interconnected parts, and where said removing step includesthe step of splitting said passage lengthwise by releasing aninterconnection between said interconnected parts.
 4. An anastomoticinstrument for connecting an end region of a first vessel to a side of asecond vessel by carrying out an end-to-side anastomosis, comprising:alongitudinal cavity in which said first vessel is carried, an anvilassembly located about said longitudinal cavity and comprising acircumferential anvil member about which an end region of said firstvessel may be everted with the terminal part of said end region facingrearwardly, rearwardly facing staple-bending recesses provided in saidanvil member and about said longitudinal cavity, clamping members aboutsaid longitudinal cavity adapted to be moved towards said anvil memberso as to make it possible to clamp together therebetween said end regionon said first vessel and an edge region on said second vessel, andstapling plungers about said longitudinal cavity movable relative tosaid anvil member and adapted to insert staples penetratingly throughsaid clamped end and edge regions into engagement with saidstapling-bending recesses so as to bend permanently said staples into ashape by which said staples hold said end and edge regions together,said stapling plungers being slidable in directions forming acute angleswith the longitudinal axis of said longitudinal cavity and converging ina region forward of said circumferential anvil member.
 5. An instrumentas claimed in claim 4, wherein said clamping members are slidable atacute angles parallel to those in which adjacent ones of said staplingplungers are slidable.
 6. An instrument as claimed in claim 4, whereinsaid anvil assembly is formed of first interconnectable partssurrounding said longitudinal cavity, said anvil member is formed ofsecond interconnectable parts surrounding said longitudinal cavity, andsaid clamping members are formed respectively of third and fourthinterconnectable parts surrounding said longitudinal cavity, andfurtherincluding a releasable interconnection between said interconnected partsso as to enable said longitudinal cavity to be split lengthwise.
 7. Aninstrument claim 5, whereina) said clamping members are provided withfirst laterally extending operating studs, b) said stapling plungers areprovided with second laterally extending operating studs, and c) saidfirst and second operating studs are adapted to cooperate with commonangular operating slots in likewise common operating slides adapted tobe operated by a manually operable mechanism common to all operatingslides such thatc1) in an initial phase of movement of said operatingslides, the clamping members move into close adjacency to said anvilmember, and c2) in a final phase of movement of said operating slides,the stapling plungers move into a staple-bending position close to saidanvil member.